U.S. patent number 10,368,452 [Application Number 15/855,931] was granted by the patent office on 2019-07-30 for foldable display device.
This patent grant is currently assigned to LG Display Co., Ltd.. The grantee listed for this patent is LG Display Co., Ltd.. Invention is credited to Seung-O Jeon, Dai-Yun Lee, Shin-Suk Lee, Young-Joon Yun.
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United States Patent |
10,368,452 |
Yun , et al. |
July 30, 2019 |
Foldable display device
Abstract
A foldable display device that reduces a transfer or distortion
phenomenon of a folding part, prevents a display panel from
sagging, and exhibits excellent folding characteristics. The
foldable display device includes a display panel including a
folding part and a non-folding part, a plurality of middle frames
disposed at the lower surface of the display panel, and a bottom
case for receiving the display panel and the middle frames. Each of
the middle frames includes a frame folding part located at a region
corresponding to the folding part of the display panel and a
plurality of plates located at a region corresponding to the
non-folding part of the display panel.
Inventors: |
Yun; Young-Joon (Paju-si,
KR), Lee; Dai-Yun (Gimpo-si, KR), Jeon;
Seung-O (Seoul, KR), Lee; Shin-Suk (Gimpo-si,
KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
LG Display Co., Ltd. |
Seoul |
N/A |
KR |
|
|
Assignee: |
LG Display Co., Ltd. (Seoul,
KR)
|
Family
ID: |
62712169 |
Appl.
No.: |
15/855,931 |
Filed: |
December 27, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20180192527 A1 |
Jul 5, 2018 |
|
Foreign Application Priority Data
|
|
|
|
|
Dec 30, 2016 [KR] |
|
|
10-2016-0184367 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F
1/1681 (20130101); H01L 51/0097 (20130101); G06F
1/1641 (20130101); G06F 1/1652 (20130101); H05K
5/0017 (20130101); G09F 9/301 (20130101); H01L
2251/5338 (20130101) |
Current International
Class: |
G06F
1/16 (20060101); H05K 5/00 (20060101); G09F
9/30 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Edwards; Anthony Q
Attorney, Agent or Firm: Fenwick & West LLP
Claims
What is claimed is:
1. A foldable display device comprising: a display panel comprising
at least one folding part and at least two non-folding parts, the
at least one folding part between the at least two non-folding
parts; a plurality of middle frames disposed at a lower surface of
the display panel; and a bottom case for receiving the display
panel and the plurality of middle frames, wherein each of the
plurality of middle frames comprises at least two flat parts and a
frame folding part between the two flat parts, wherein each of the
at least two flat parts of each middle frame overlaps a
corresponding one of the at least two non-folding parts of the
display panel, and wherein the frame folding part of the middle
frame overlaps the at least one folding part of the display panel,
and wherein one of the plurality of middle frames has a different
length than other middle frames from the plurality of middle
frames.
2. The foldable display device according to claim 1, wherein the
frame folding part comprises a folding pattern comprising a
plurality of bars arranged in parallel to a folding axis, about
which the display panel is folded, and an opening pattern
comprising a plurality of slits alternating with the bars of the
folding pattern, and the flat part comprises a plurality of plates
provided at opposite sides of the folding pattern.
3. The foldable display device according to claim 2, wherein the
opening patterns provided at one of the middle frames are
misaligned with the opening patterns provided at another one of the
middle frames.
4. The foldable display device according to claim 2, wherein the
plurality of middle frames comprise: a main frame laminated to the
lower surface of the display panel via a first adhesive layer; and
at least one sub frame provided between the main frame and a bottom
surface of the bottom case.
5. The foldable display device according to claim 4, wherein the at
least one sub frame comprises a support layer disposed at one
surface of the frame folding part and one surface of each of the
plates for supporting the frame folding part and the plates.
6. The foldable display device according to claim 5, wherein each
of the display panel and the main frame comprises an extension
extending from one side thereof further than the at least one sub
frame.
7. The foldable display device according to claim 6, wherein the
bottom case comprises a protrusion protruding toward and supporting
the extension of each of the display panel and the main frame.
8. The foldable display device according to claim 7, wherein: the
main frame comprises a first plate comprising the extension and a
second plate located opposite the first plate with the frame
folding part disposed between the first plate and the second plate,
and the extension of the main frame is laminated to the protrusion
via a second adhesive layer.
9. The foldable display device according to claim 8, wherein the
frame folding part of the at least one sub frame and the plate of
the at least one sub frame overlapping the first plate
independently slip relative to an adjacent one of the middle frames
when the foldable display device is folded along the folding
axis.
10. The foldable display device according to claim 8, wherein the
at least one sub frame comprises a first sub frame that contacts
the main frame, wherein the first sub frame comprises a third plate
overlapping the first plate and a fourth plate overlapping the
second plate, wherein the fourth plate is laminated to the second
plate via a third adhesive layer.
11. The foldable display device according to claim 10, wherein the
at least one sub frame further comprises at least one second sub
frame provided between the first sub frame and the bottom surface
of the bottom case.
12. The foldable display device according to claim 11, wherein the
at least one second sub frame comprises a fifth plate overlapping
the first plate and a sixth plate overlapping the second plate,
wherein the sixth plate is laminated to a plate of an adjacent one
of the middle frames via a fourth adhesive layer.
13. The foldable display device according to claim 12, wherein the
sixth plate is laminated to an adjacent one of the middle frames
via a fifth adhesive layer.
14. The foldable display device according to claim 12, wherein the
sixth plate is laminated to the bottom surface of the bottom case
via a fifth adhesive layer.
15. The foldable display device according to claim 1, wherein the
frame folding part is arranged in parallel with a folding axis of
the foldable display device.
16. A foldable display device comprising: a display panel including
a first folding part, a first non-folding part and a second
non-folding part, the first non-folding part extending in a first
direction from the first folding part and the second non-folding
part extending in a second direction from the first folding part
opposite the first direction, the display panel configured to be
folded along a folding axis within the first folding part; a main
frame attached to a lower surface of the display panel, the main
frame including a second folding part, a first non-folding plate
and a second non-folding plate, the first non-folding plate
extending in the first direction from the second folding part and
the second non-folding plate extending in the second direction from
the second folding part; a first sub-frame under the main frame and
including a third folding part, a third non-folding plate and a
fourth non-folding plate, the third non-folding plate extending in
the first direction from the third folding part and the fourth
non-folding plate extending in the second direction from the third
folding part; and a bottom case for receiving the display panel,
the main frame, and the first sub-frame, wherein: the display panel
and the first non-folding plate of the main frame extend longer in
the first direction than the third non-folding plate of the first
sub-frame; the fourth non-folding plate of the first sub-frame is
attached to the second non-folding plate of the main frame; the
third folding part of the first sub-frame is not attached to the
second folding part of the main frame; and the third non-folding
plate of the first sub-frame is not attached to the first
non-folding plate of the main frame.
17. The foldable display device according to claim 16, wherein the
bottom case comprises a protrusion protruding toward and supporting
an extension part of the first non-folding plate of the main frame
extending longer in the first direction than the third non-folding
plate of the first sub-frame.
18. The foldable display device according to claim 17, wherein the
extension part of the first non-folding plate of the main frame is
attached to the protrusion of the bottom case.
19. The foldable display device according to claim 16, wherein the
third folding part and the third non-folding plate of the first
sub-frame slip in the first direction relative to the main frame
when the foldable display device is folded along the folding
axis.
20. The foldable display device according to claim 16, wherein: the
second folding part of the main frame includes a plurality of first
bars arranged along the folding axis and a plurality of first slits
alternating with the first bars; the third folding part of the
first sub-frame includes a plurality of second bars arranged along
the folding axis and a plurality of second slits alternating with
the second bars; and the first bars of the main frame are
misaligned with the second bars of the first sub-frame.
21. The foldable display device according to claim 16, wherein the
first sub-frame includes a support layer disposed on a surface of,
and supporting, the third folding part, the third non-folding
plate, and the fourth non-folding plate.
Description
This application claims the benefit of Korean Patent Application
No. 10-2016-0184367, filed on Dec. 30, 2016, which is hereby
incorporated by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a foldable display device, and
more particularly to a foldable display device that is capable of
increasing the support force of a display panel in the vertical
direction and minimizing the stress applied to a folding part when
folded.
Discussion of the Related Art
Image display devices are a core technology in the information and
communication age for displaying various kinds of information on a
screen. Image display devices have been developed such that they
are thinner, lighter, and portable and exhibit high performance.
Organic light-emitting display devices control the amount of light
that is emitted from an organic light-emitting layer to display an
image. Organic light-emitting display devices have been highlighted
as flat panel display devices, which are lighter and smaller than
cathode ray tubes (CRT).
In an organic light-emitting display device, a plurality of pixels
are arranged in the form of a matrix to display images. Each pixel
includes a light-emitting device, and the organic light-emitting
display device includes a pixel drive circuit including a plurality
of transistors configured to independently drive the respective
light-emitting device of each pixel.
Using a self-emitting organic light-emitting device, an organic
light-emitting display device does not need an additional light
source, and may be realized as an ultra-thin display device. In
recent years, therefore, research has been actively conducted into
an in-cell touch type foldable display device, which uses an
organic light-emitting device and includes a touch electrode array
in a light-emitting cell.
A foldable display device has a structure in which the display
device itself, including a display panel, is foldable. In order to
protect such a flexible display panel, a middle frame is provided.
The middle frame, which is provided at the lower surface of the
display panel to protect the display panel, must be designed to be
foldable.
In a conventional foldable display device, the region of a middle
frame corresponding to the folding part has a soft structure
including silicone resin, and the remaining region of the middle
frame corresponding to a non-folding part is made of metal or rigid
plastic to protect the display panel.
In the conventional foldable display device using the middle frame,
the folding part and the non-folding part are formed of different
materials. The materials are different from each other in terms of
their physical properties, such as rigidity, elasticity, and
softness. In addition, the material is compressed differently
during the processing. As a result, there is a high possibility of
irregularities being formed at the interface between the different
materials. When the irregularities are formed between the folding
part and the non-folding part, a display screen may become
transferred or distorted. In addition, when the conventional
foldable display device using the middle frame is folded multiple
times, the soft folding part is stressed, with the result that the
display panel may swell or sag. Furthermore, the soft folding part
may be deformed or hardened under high-temperature, high-humidity
conditions.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a foldable
display device that substantially obviates one or more problems due
to limitations and disadvantages of the related art.
An object of the present invention is to provide a foldable display
device that reduces a transfer or distortion phenomenon of a
folding part, prevents a display panel from sagging, and exhibits
excellent folding characteristics.
Additional advantages, objects, and features of the invention will
be set forth in part in the description which follows and in part
will become apparent to those having ordinary skill in the art upon
examination of the following or may be learned from practice of the
invention. The objectives and other advantages of the invention may
be realized and attained by the structure particularly pointed out
in the written description and claims hereof as well as the
appended drawings.
In one embodiment, a foldable display device includes a display
panel including at least one folding part and at least two
non-folding parts, a plurality of middle frames disposed at the
lower surface of the display panel, and a bottom case for receiving
the display panel and the middle frames. Each of the middle frames
includes a frame folding part located at a region corresponding to
the folding part of the display panel and a plurality of plates
located at regions corresponding to the non-folding parts of the
display panel.
The frame folding part may include a folding pattern including a
plurality of bars arranged in parallel to a folding axis, about
which the display panel is folded, and an opening pattern including
a plurality of slits alternating with the bars of the folding
pattern. The opening patterns provided at one of the middle frames
may be misaligned with the opening patterns provided at another one
of the middle frames.
The main frame may include an extension that extends from one side
thereof further than the sub frame, and the extension may be held
by a protrusion formed on the bottom case. A frame folding part of
the sub frame and a plate of the sub frame that is adjacent to the
protrusion may independently slip relative to an adjacent one of
the middle frames at the time of folding.
In another embodiment, a foldable display device comprises a
display panel, main frame, a first sub-frame, and a bottom cover.
The display panel includes a first folding part, a first
non-folding part and a second non-folding part, the first
non-folding part extending in a first direction from the first
folding part and the second non-folding part extending in a second
direction from the first folding part opposite the first direction.
The display panel is configured to be folded along a folding axis
within the first folding part. The main frame is attached to a
lower surface of the display panel. The main frame includes a
second folding part, a first non-folding plate and a second
non-folding plate, the first non-folding plate extending in the
first direction from the second folding part and the second
non-folding plate extending in the second direction from the second
folding part. The first sub-frame is under the main frame and
includes a third folding part, a third non-folding plate and a
fourth non-folding plate. The third non-folding plate extends in
the first direction from the third folding part and the fourth
non-folding plate extends in the second direction from the third
folding part. The bottom case receives the display panel, the main
frame, and the first sub-frame. The display panel and the first
non-folding plate of the main frame extend longer in the first
direction than the third non-folding plate of the first sub-frame.
The fourth non-folding plate of the first sub-frame is attached to
the second non-folding plate of the main frame. The third folding
part of the first sub-frame is not attached to the second folding
part of the main frame. The third non-folding plate of the first
sub-frame is not attached to the first non-folding plate of the
main frame.
The bottom case may comprise a protrusion protruding toward and
supporting an extension part of the first non-folding plate of the
main frame extending longer in the first direction than the third
non-folding plate of the first sub-frame. The extension part of the
first non-folding plate of the main frame is attached to the
protrusion of the bottom case.
The third folding part and the third non-folding plate of the first
sub-frame slip in the first direction relative to the main frame
when the foldable display device is folded along the folding
axis.
The second folding part of the main frame includes a plurality of
first bars arranged along the folding axis and a plurality of first
slits alternating with the first bars. The third folding part of
the first sub-frame includes a plurality of second bars arranged
along the folding axis and a plurality of second slits alternating
with the second bars. The first bars of the main frame are
misaligned with the second bars of the first sub-frame.
In some embodiments, the first sub-frame includes a support layer
disposed on a surface of, and supporting, the third folding part,
the third non-folding plate, and the fourth non-folding plate.
It is to be understood that both the foregoing general description
and the following detailed description of the present invention are
exemplary and explanatory and are intended to provide further
explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further
understanding of the invention and are incorporated in and
constitute a part of this application, illustrate embodiment(s) of
the invention and together with the description serve to explain
the principle of the invention. In the drawings:
FIG. 1 is an exploded perspective view of a foldable display device
according to an embodiment of the present invention;
FIG. 2A is a schematic view illustrating the assembled structure of
the foldable display device shown in FIG. 1, and FIG. 2B is a
schematic view illustrating the form of the foldable display device
shown in FIG. 2A when folded;
FIG. 3 is a sectional view of the foldable display device according
to an embodiment of the present invention, illustrating the
position and coupling relationship of middle frames in detail;
FIG. 4 is a sectional view illustrating the misalignment of opening
patterns in the middle frames; and
FIG. 5 is a schematic view illustrating a change in the shape of a
display panel, a main frame, and sub frames when the foldable
display device according to an embodiment of the present invention
is folded.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiments
of the present invention, examples of which are illustrated in the
accompanying drawings. Wherever possible, the same reference
numbers will be used throughout the drawings to refer to the same
or like parts. In the following description of the present
invention, a detailed description of known functions and
configurations incorporated herein will be omitted when it may
obscure the subject matter of the present invention. In addition,
the terms used in the following description are selected in
consideration of ease of preparation of the specification, and may
be different from the names of parts constituting an actual
product.
It will be understood that when an element is referred to as being
"on" another element, it may be directly on the element, or one or
more intervening layers or elements may also be present
therebetween. In contrast, it will be understood that when an
element is referred to as "contacting" another element, no
intervening elements or layers are present therebetween.
The size and thickness of each element shown in the drawings are
given merely for the convenience of description, and the present
invention is not limited thereto.
FIG. 1 is an exploded perspective view of a foldable display device
according to an embodiment of the present invention.
The foldable display device according to the present invention
includes a display panel 100 including at least one foldable
folding part F/A and at least two non-folding parts N/F, which are
the remaining regions excluding the foldable folding part F/A, a
cover window 3000 laminated to the upper surface of the display
panel, the cover window 3000 including a folding part F/A
corresponding to the folding part F/A of the display panel 100 and
non-folding parts N/F corresponding to the non-folding parts N/F of
the display panel 100, a plurality of middle frames 200 laminated
to the lower surface of the display panel 100, a bottom case 1000
for receiving the display panel 100, the cover window 3000, and the
middle frames 200, and a top case 1100 fastened to the bottom case
1000, the top case 1100 disposed on the cover window 3000 to cover
the edge of a top surface of the cover window 3000.
The folding part F/A of the display panel 100 is flexible, i.e.
foldable. The non-folding parts N/F of the display panel 100 are
formed so as to have higher rigidity than the folding part F/A.
However, the present invention is not limited thereto. Depending on
the design, the folding part F/A and the non-folding parts N/F of
the display panel 100 may be formed so as to be flexible, and the
portions of the middle frames 1000 corresponding to the non-folding
parts N/F may be rigid to thus support the non-folding parts N/F of
the display panel 100.
The non-folding parts N/F of the display panel 100 may be located
parallel to the folding axis of the folding part F/A, and may be
located at opposite sides of the folding part F/A.
The display panel 100, which is flexible, displays images. In one
embodiment, the display panel 100 is an organic light-emitting
display panel. However, the present invention is not limited
thereto. Various kinds of display panels, such as a liquid crystal
display panel and an electrophoretic display panel, may be used.
Images displayed on the display panel 100 are visible to a user
through the cover window 3000.
The cover window 3000 may include a folding part F/A corresponding
to the folding part F/A of the display panel 100. The folding part
F/A of the cover window 3000 may include a flexible soft part. The
remaining regions of the cover window 3000, i.e. the non-folding
parts N/F, may include a hard part that exhibits higher rigidity
than the soft part. However, the present invention is not limited
thereto. The cover window 3000 is located on the display panel 100
to protect the display panel 100 from external shocks and the
external environment. The cover window 3000 may be made of a
transparent material, such as glass or polymer resin.
The middle frames 200 are located at the lower surface of the
display panel 100. In FIG. 1, three middle frames are shown by way
of example. However, the present invention is not limited thereto.
Depending on the design, the number of middle frames 200 may range
from 2 to 5.
Each middle frame 200 includes a frame folding part 2010 and flat
parts 2110 located at opposite sides of the frame folding part
2010. The flat parts 2110 are formed so as to include plates 2111a
to 2111f. Each middle frame 200 may be made of a material that
exhibits high rigidity, such as metal. However, the present
invention is not limited thereto.
The frame folding part 2010 enables each middle frame 200 to be
folded while supporting the folding part F/A of the display panel
100. To this end, the frame folding part 2010 includes a folding
pattern 2011 and an opening pattern 2012. The opening pattern 2012
is formed by removing a portion of the material constituting each
middle frame 200 such that the lower surface of the display panel
100 is exposed. The opening pattern 2012 may be linearly formed
parallel to the folding axis of the display panel. That is, the
opening pattern 2012 may be configured in the form of slits, which
are provided parallel to the folding axis and open a portion of the
lower surface of the display panel 100.
A portion of the material constituting each middle frame 200 is
removed from the frame folding part 2010 in order to form the
opening pattern 2012, and the remaining portion constitutes the
folding pattern 2011. The folding pattern 2011 may be configured in
the shape of a plurality of bars spaced apart from each other,
since the opening pattern 2012 is formed linearly. However, the
present invention is not limited thereto. Adjacent ones of the bars
constituting the folding pattern 2011 may be partially adhered to
each other, and the opening pattern 2012 may be further provided
with a thin film remaining and (not shown) having a thickness less
than that of each middle frame 200. In addition, the folding
pattern 2011 and the opening pattern 2012 may have various forms
depending on the design.
In FIG. 1, the folding pattern 2011 is exaggerated. However, the
actual width of the folding pattern 2011 in the shorter direction
is about 0.3 mm or less, which is very small. The opening pattern
2012 has a small width of about 0.1 mm in the shorter direction.
That is, the folding pattern 2011 and the opening pattern 2012 are
micro patterns.
Since the folding pattern 2011 and the opening pattern 2012 are
formed so as to have micro-scale sizes, the folding part F/A of the
display panel 100 is effectively supported by the folding pattern
2011 in the unfolded state. In the folded state, on the other hand,
the bars of the folding pattern 2011, which are separated from each
other by the opening pattern 2012, are independently folded along
the display panel 100 (i.e., along the longer direction of each bar
of the folding pattern 2011) without applying stress to each other.
Consequently, the bars of the folding pattern 2011 support the
display panel 100 with minimized stress when the display panel 100
is folded, and enable each middle frame 200 to be easily
folded.
The plates 2111a to 2111f of the flat parts 2110 are located so as
to correspond to the lower surface of the non-folding parts N/F of
the display panel 100. Each of the plates 2111a to 2111f is made of
a material that exhibits high rigidity, such as metal, to support
the display panel 100 and to protect the display panel 100 from
external shocks. The flat parts 2110 are located at opposite sides
of the frame folding part 2010. Consequently, the plates 2111a to
2111f provided at the flat parts 2110 are also located at opposite
sides of the frame folding part 2010.
The plates 2111a to 2111f are located to correspond only to the
lower surface of the non-folding parts N/F of the display panel
100, whereby the plates 2111a to 2111f do not extend to or overlap
with the folding parts F/A of the display panel 100 and as such the
folding of the display panel 100 is not affected.
In this specification, one of the middle frames 200 that contacts
the lower surface of the display panel 100 is defined as a main
frame 201, and the other middle frames 200 are defined as sub
frames 202 and 203. One of the sub frames that contacts the main
frame 201 is defined as a first sub frame 202, and the other sub
frame is defined as a second sub frame 203.
The main frame 201 has the same length and width as the display
panel 100 such that the main frame 201 is laminated to the entire
lower surface of the display panel 100. Although not shown, a first
adhesive layer is provided between the main frame 201 and the
display panel 100. The first adhesive layer is provided on the
entire lower surface of the display panel 100 to laminate the main
frame 201 to the display panel 100. The main frame 201 includes a
first frame folding part 2010a and first flat parts 2110a. The
first frame folding part 2010a is located so as to correspond to
the folding part F/A of the display panel 100, and the first flat
parts 2110a are located so as to correspond to the non-folding
parts N/F of the display panel 100.
The first flat parts 2110a include a first plate 2111a and a second
plate 2111b. In addition, the first frame folding part 2010a
includes a first folding pattern 2011a and a first opening pattern
2012a, which have the previously described characteristics of the
folding pattern and the opening pattern.
The first sub frame 202 is laminated to the lower surface of the
main frame 201. The first sub frame 202 includes a second frame
folding part 2010b and second flat parts 2110b.
The second frame folding part 2010b includes a second folding
pattern 2011b and a second opening pattern 2012b, which have the
previously described characteristics of the folding pattern and the
opening pattern. The second flat parts 2110b include a third plate
2111c and a fourth plate 2111d.
The second sub frame 203 may be laminated to the lower surface of
the first sub frame 202. In the case in which a plurality of second
sub frames 203 are provided, the second sub frames 203 may be
laminated to each other.
The second sub frame 203 includes a third frame folding part 2010c
and third flat parts 2110c. The third frame folding part 2010c
includes a third folding pattern 2011c and a third opening pattern
2012c, which have the previously described characteristics of the
folding pattern and the opening pattern. The third flat parts 2110c
include a fifth plate 2111e and a sixth plate 2111f.
The first and second sub frames 202 and 203 are formed so as to
have a length less than that of the display panel 100 and the main
frame 201. Referring to FIG. 1, one of the plates 2111c to 2111f
provided at the flat parts 2110b and 2110c of the first and second
sub frames 202 and 203, respectively (e.g. the third plate 2111c of
the first sub frame 202 and the fifth plate 2111e of the second sub
frame 203) are formed so as to have a length less than that of one
of the plates of the main frame 201, which is located above the
first and second sub frames 202 and 203 (e.g. the first plate
2111a). That is, the display panel 100 includes a first extension
101 that extends from one side thereof further than the first and
second sub frames 202 and 203. In addition, one of the plates 2111a
and 2111b of the main frame 201, e.g. the first plate 2111a, also
includes a second extension 2013 that extends from one side thereof
further than the first and second sub frames 202 and 203. The first
and second extensions 101 and 2013 are held by a protrusion 1005 of
the bottom case 1000 to support the main frame 201 and the display
panel 100, which will be described in detail when describing the
bottom case 1000.
The bottom case 1000 receives therein the middle frames 200, the
display panel 100, and the cover window 3000. The bottom case 1000
includes a first hinge 1001a and a second hinge 1001b, which are
provided so as to correspond to the folding part F/A of the display
panel 100 to fold the display panel 100. The hinges 1001a and 1001b
are located so as to correspond to opposite sides of the folding
part F/A of the display panel 100 such that the bottom case 1000
can be folded when the middle frames 200, the display panel 100,
and the cover window 3000 are folded. However, the present
invention is not limited thereto. In the case in which the hinges
1001a and 1001b are located so as to correspond to opposite sides
of the folding part F/A of the display panel 100, the bottom case
1000 may be configured such that the bottom case 1000 is divided
into two separate parts, which rotate around the hinges 1001a and
1001b in opposite directions (i.e., counterclockwise and clockwise)
when folded.
The bottom case 1000 is provided with a protrusion 1005 at the
bottom surface of the portion corresponding to the lower side of
the extensions 101 and 2013 of the display panel 100 and the main
frame 201, respectively. The protrusion 1005 is adhered to the
second extension 2013 of the main frame 201 to support and fix the
first extension 101 of the display panel 100 and the second
extension 2013 of the main frame 201.
The plates of the sub frames 202 and 203 located opposite the
protrusion 1005, e.g. the fourth plates 2111d and the sixth plates
2111f, are laminated to other adjacent middle frames 201, 202, and
203. Referring to FIG. 1, the first sub frame 202 is laminated to
the main frame 201 and to the second sub frame 203. The fourth
plate 2111d of the first sub frame 202 is laminated to the second
plate 2111b of the main frame 201. In addition, the fourth plate
2111d is also laminated and fixed to the sixth plate 2111f of the
second sub frame 203, which is located at the lower side of the
first sub frame 202.
The second sub frame 203 is laminated to the first sub frame 202.
The sixth plate 2111f of the second sub frame 203 is laminated to
the fourth plate 2111d of the first sub frame 202.
An additional second sub frame may be further provided at the lower
side of the second sub frame 203. In this case, the sixth plate
2111f may be laminated to an adjacent plate of the additional
second sub frame.
Alternatively, in the case in which the second sub frame 203
contacts the bottom surface of the bottom case 1000, the sixth
plate 2111f is laminated to the bottom surface of the bottom case
1000.
Consequently, only the plates of the first and second sub frames
202 and 203 that are located opposite the protrusion 1005, e.g. the
fourth plate 2111d of the first sub frame 202 and the sixth plate
2111f of the second sub frame 203, are supported and fixed. The
other plates, which are located adjacent to the protrusion 1005,
e.g. the third plate 2111c and the fifth plate 2111e of the first
sub frame 202, the second frame folding part 2010b of the first sub
frame 202, and the third frame folding part 2010c of the second sub
frame 203 are not fixed using the adhesive layer but independently
slip in response to folding of the middle frames 201, 202, and 203,
i.e. the main frame 201 and the first and second sub frames 202 and
203.
On the other hand, one side of the display panel 100 and the main
frame 201 is attached to the fourth plate 2111d of the first sub
frame 202, which is located opposite the protrusion 1005, and the
other side of the display panel 100 and the main frame 201 is
attached to the protrusion 1005. Since the fourth plate 2111d is
attached to the sixth plate 2111f of the second sub frame 203 and
the sixth plate 2111f is attached to the bottom surface of the
bottom case 1000, as described above, the first plate 2111a of the
main frame 201 of the display panel 100 is attached to the
protrusion 1005, and the second plate 2111b of the main frame 201
of the display panel 100 is fixed to the bottom surface of the
bottom case 1000 via the fourth and sixth plates 2111d and 2111f of
the sub frames 202 and 203, which are located under the main frame
201. As a result, the entirety of the main frame 201 is fixed and
thus does not slip.
To this end, although not shown in FIG. 1, adhesive layers (not
shown) may be further provided between the display panel 100 and
the main frame 201, between one of the plates of the main frame
201, e.g. the second plate 2111b, and one of the plates of the
first sub frame 202, e.g. the fourth plate 2111d, and between the
plates of the first and second sub frames 202 and 203, e.g. the
fourth plate 2111d and the sixth plate 2111f. The structure of the
main frame 201 and the sub frames 202 and 203 will be described
below in detail.
The top case 1100 can be folded simultaneously when the display
panel 100 is folded. To this end, the region of the top case 1100
corresponding to the folding part F/A of the display panel 100 may
be configured to be foldable. For example, the top case 1100 may be
configured such that the top case 1100 is divided into two parts
about the region thereof corresponding to the folding part F/A of
the display panel 100, may be made of a flexible material, or may
be provided with an additional hinge (not shown), about which the
top case 1100 is foldable. However, the present invention is not
limited thereto.
FIG. 2A is a schematic view illustrating the assembled structure of
the foldable display device shown in FIG. 1, and FIG. 2B is a
schematic view illustrating the form of the foldable display device
shown in FIG. 2A when folded.
When the foldable display device according to the present invention
is assembled, as shown in FIG. 2A, the cover window 3000 is visible
through the bottom case 1000, the top case 1100, and the central
part of the foldable display device, at which the top case 1100 is
not formed.
Although not shown in FIG. 2A, the display panel 100 is located at
the lower side of the cover window 3000, and displays images
through the cover window 3000. The hinge 1001a provided at the
bottom case 1000 may be alternatively located in the top case 1100
so as not to be visible, or may protrude outward from the top case
1100. However, the present invention is not limited thereto. Since
it is also necessary for the top case 1100 to be folded, the top
case 1100 may be divided into two parts about the hinge 1001a, the
region of the top case 1100 corresponding to the folding part F/A
of the display panel 100 may be made of a flexible material, or the
top case 1100 may be provided with an additional hinge (not shown).
However, the present invention is not limited thereto.
The bottom case 1000 may be formed so as to be divided into two
parts about the hinge 1001a.
Since the bottom case 1000 and the top case 1100 are configured as
described above, the bottom case 1000 and the top case 1100 may be
folded simultaneously with the display panel 100, the cover window
3000, and the middle frames 2000 when the foldable display device
according to the present invention is folded as shown in FIG.
2B.
FIG. 3 is a sectional view of the foldable display device according
to the present invention, illustrating the position and coupling
relationship of the middle frames 200 in detail.
Referring to FIG. 3, the second sub frame 203, the first sub frame
202, the main frame 201, the display panel 100, and the cover
window 300 are sequentially stacked in the bottom case 1000. The
cover window 300 and the display panel 100 are laminated to each
other via a panel adhesive layer 110. The edges of the display
panel 100 and the cover window 300 are covered by the top case
1100. The top case 1100 serves to protect the surface of the
foldable display device on which images are displayed.
The display panel 100 is laminated to the main frame 201 via a
first adhesive layer 111. The first adhesive layer 111 is disposed
on the entire lower surface of the display panel 1000 to securely
laminate the display panel 100 to the main frame 201. The first
extension 101 is provided at one side of the display panel 100 so
as to protrude further than the sub frames 202 and 203. A cover
extension 3013 of the cover window 3000 may be further provided at
the upper side of the first extension 101 of the display panel
101.
The main frame 201 includes a frame folding part 2010 and plates
2111. One of the plates 2111, i.e. a first plate 2111a, includes a
second extension 2013 protruding further than the sub frames 202
and 203 in the horizontal direction. The second extension 2013 of
the main frame 201 is held by the protrusion 1005, which is defined
by the bottom surface protruding from the bottom case 1000. Between
the second extension 2013 of the main frame 201 and the protrusion
1005 is provided a second adhesive layer 112, via which the second
extension 2013 of the main frame 201 is adhered and fixed to the
protrusion 1005.
The main frame 201 includes a second plate 2111b, which is located
opposite the second extension 2013 of the first plate 2111a in the
horizontal direction and is spaced apart from the first plate 2111a
in the state in which the first frame folding part 2010a is
disposed therebetween. Each of the first and second plates 2111a
and 2111b may be made of a material that exhibits high rigidity,
such as metal. The first plate 2111a, the second plate 2111b, and
the first frame folding part 2010a are laminated to the display
panel 1000 via the first adhesive layer 111.
Since the display panel 100 is laminated to the main frame 201, the
display panel 100 is also supported and fixed by the protrusion
1005 together with the main frame 201.
As previously described, the first frame folding part 2010a of the
main frame 201 includes a first folding pattern 2011a and a first
opening pattern 2012a. The bars of the first folding pattern 2011a
may be spaced apart from each other in the state in which the bars
are interposed between the respective slits of the first opening
pattern 2012a. Since the bars of the first folding pattern 2011a
are spaced apart from each other, the first folding pattern 2011a
supports the display panel 1000 in the unfolded state, and adjacent
bars of the first folding pattern 2011a do not apply stress to each
other in the folded state. Consequently, the stress applied to the
first frame folding part 2010a is minimized.
The first sub frame 202 includes a third plate 2111c, a fourth
plate 2111d, and a second frame folding part 2010b. The second sub
frame 203 includes a fifth plate 2111e, a sixth plate 2111f, and a
third frame folding part 2010c.
As also mentioned with reference to FIG. 1, one of the plates 2111
of the first sub frame 202 that overlaps the first plate 2111a of
the main frame 201 is defined as a third plate 2111c, and one of
the plates 2111 of the first sub frame 202 that overlaps the second
plate 2111b of the main frame 201 is defined as a fourth plate
2111d, for the convenience of description. In addition, one of the
plates 2111 of the second sub frame 203 that overlaps the first
plate 2111a is defined as a fifth plate 2111e, and one of the
plates 2111 of the second sub frame 203 that overlaps the second
plate 2111b is defined as a sixth plate 2111f.
The first sub frame 202 is configured such that the bars of the
second folding pattern 2011b of the second frame folding part 2010b
are completely divided from each other by the slits of the second
opening pattern 2012b and such that second frame folding part 2010b
is not attached to the first frame folding part 2010a of the main
frame 201 or to the third frame folding part 2010c of the second
sub frame 203. Unless the second folding pattern 2011b is fixed,
the second folding pattern 2011b moves and thus cannot exhibit its
function. Consequently, a first support layer 2024a may be provided
on the second folding pattern 2011b and the second opening pattern
2012b to support and fix the second folding pattern 2011b such that
the shape and position of the second folding pattern 2011b are
maintained. The first support layer 2024a is attached to both the
second frame folding part 2010b and the second flat parts 2110b to
maintain the shape of the first sub frame 202.
For the same reason as the first sub frame 202, the second sub
frame 203 may further include a second support layer 2024b for
supporting and fixing the third flat parts 2110c and the third
frame folding part 2010c.
In FIG. 3, the first and second support layers 2024a and 2024b are
shown as being attached to the upper surfaces of the sub frames 202
and 203, respectively. However, the present invention is not
limited thereto. The first and second support layers 2024a and
2024b may be attached to the lower surfaces of the sub frames 202
and 203, respectively.
The lower surface of the second plate 2111b of the main frame 201
is adhered to the first support layer 2024a of the first sub frame
202. The second plate 2111b of the main frame 201 is laminated to
the first support layer 2024a of the first sub frame 202 via a
third adhesive layer 112. The third adhesive layer 112 is located
at the region that overlaps the second plate 2111b. In order words,
the first plate 2111a and the first frame folding part 2010a of the
main frame 201 are not adhered to the first support layer 2024a of
the first sub frame 202.
Consequently, the fourth plate 2111d, which is located at the lower
side of the second plate 2111b, is adhered and fixed to the second
plate 2111b via the first support layer 2024a.
The third plate 2111c and the second frame folding part 2010b of
the first sub frame 202 are not fixed to other elements, and thus
slip in the horizontal direction in response to folding of the
bottom case 1000.
Meanwhile, the second sub frame 203 may be omitted. In this case,
the fourth plate 2111d of the first sub frame 202 may be laminated
to the bottom surface of the bottom case 2000 via an adhesive
layer. Even in this case, the adhesive layer, which is provided
between the bottom surface and the fourth plate 2111d, may be
located only at the region that overlaps the fourth plate 2111d.
Consequently, the second frame folding part 2010b and the third
plate 2111c of the first sub frame 202 are not fixed to other
elements, and therefore slip in the horizontal direction in
response to folding of the bottom case 1000.
Referring to FIG. 3, in some embodiments at least one second sub
frame 203 may be further provided between the first sub frame 202
and the bottom case 1000. In FIG. 3, an example in which only a
single second sub frame 203 is provided is shown. Alternatively,
two or more second sub frames 203 may be provided. In addition,
only the main frame 201 and the first sub frame 202 may be
provided, and the second sub frame 203 may be omitted.
As shown in FIG. 3, the second support layer 2024b of the second
sub frame 203 is laminated to the fourth plate 2111d of the first
sub frame 202 via a fourth adhesive layer 114. The fourth adhesive
layer 114 is located only at the region that overlaps the fourth
plate 2111d and the sixth plate 2111f. Consequently, the sixth
plate 2111f is adhered and fixed to the fourth plate 2111d, but the
third plate 2111c of the first sub frame 202 is not attached to the
fifth plate 2111e of the second sub frame 203. In addition, the
first sub frame 202 is not attached to the third frame folding part
2010c of the second sub frame 203. Consequently, the second and
third frame folding parts 2010b and 2010c of the first and second
sub frames 202 and 203 are not fixed to other elements, and
therefore slip in the horizontal direction in response to folding
of the bottom case 1000.
In the case in which only a single second sub frame 203 is
provided, one of the plates 2111 of the second sub frame 203 that
is located so as to overlap the third adhesive layer 113, i.e. the
sixth plate 2111f, is laminated to the bottom surface of the bottom
case 1000 via a fifth adhesive layer 115.
That is, the second, fourth, and sixth plates 2111b, 2111d, and
2111f are fixed to the bottom surface of the bottom case 1000 via
the third adhesive layer 113, the fourth adhesive layer 114, and
the fifth adhesive layer 115, respectively. The fifth adhesive
layer 115 is also provided only at the region that overlaps the
sixth plate 2111f. As a result, the second and third frame folding
parts 2010b and 2010c and the third and fifth plates 2111c and
2111e may move without being fixed to other elements, other than
being supported by the support layers 2024a and 2024b.
Consequently, the protrusion 1005 and the first plate 2111a are
adhered and fixed to each other, and the second plate 2111b is
fixed to the bottom surface of the bottom case 1000 via the third
adhesive layer 113, whereby the display panel 100 and the main
frame 201 are fixed and are thus not movable. In contrast, the
first and second sub frames 202 and 203 are folded simultaneously
when the bottom case 1000 is folded, and the second and third frame
folding parts 2010b and 2010c and the third and fifth plates 2111c
and 2111e slip due to the force applied at the time of folding,
whereby the stress generated at the time of folding is dispersed
and thus reduced. Consequently, the foldable display device
according to the present invention has the effect of greatly
reducing the amount of stress generated at the time of folding due
to the slippage of the first and second sub frames 202 and 203.
Meanwhile, although not shown in FIG. 3, a plurality of second sub
frames 203 may be provided, as previously described. In this case,
one of the plates 2111 of the second sub frame 203 that is located
so as to overlap the third adhesive layer 113, i.e. the sixth plate
2111f, may be laminated to a support layer (not shown) of another
middle frame via the fifth adhesive layer 115. For one of the
second sub frames 203 that contacts the bottom case 1000, the plate
that overlaps the third adhesive layer 113 may be laminated to the
bottom surface of the bottom case via another adhesive layer. Even
in this case, the fifth adhesive layer 115 may be formed only at
the region that overlaps the sixth plate 2111f. As a result, the
fifth adhesive layer 115 is not provided at the fifth plate 2111e
or the third frame folding part 2010c. Consequently, the fifth
plate 2111e and the third frame folding part 2010c may slip due to
the force applied at the time of folding.
FIG. 4 is a sectional view illustrating the misalignment of the
opening patterns 2012 in the middle frames 201, 202, and 203.
In the case in which the opening patterns 2012 in the middle frames
201, 202, and 203 are aligned so as to overlap each other, the
force that supports the display panel 100 in the vertical direction
may be reduced at the region at which the opening patterns 2012 are
aligned. In this case, the region of the display panel 100
corresponding to the opening patterns 2012 may be stepped due to
low support force of the opening patterns 2012, whereby the folding
part F/A of the flexible display panel 100 may become irregular.
For this reason, it is necessary to increase the support force,
which is reduced by the opening patterns 2012, by arranging the
folding patterns 2011 under the opening patterns 2012. In order
words, the opening patterns 2012 in the middle frames 201, 202, and
203 are arranged so as to be purposely misaligned with each other,
whereby the foldable display device according to the present
invention has the effect of preventing the occurrence of a transfer
or distortion phenomenon due to the irregularities of the display
panel.
FIG. 5 is a schematic view illustrating a change in the shape of
the display panel 100, the main frame 201, and the sub frames 202
and 203 when the foldable display device according to the present
invention is folded. For the convenience of description, only the
display panel 100, the main frame 201, and the sub frames 202 and
203 are shown, and the adhesive layers and the support layers are
omitted.
Referring to the left-side figure of FIG. 5, the main frame 201 and
the sub frames 202 and 203 support the display panel 100 in the
unfolded state. In particular, the opening patterns 2012 provided
at the frame folding parts 2010 are shifted in the horizontal
direction so as to be misaligned with each other, whereby at least
one of the folding patterns 2011 is located over the entire lower
surface of the folding part F/A of the display panel 100.
Consequently, the force that supports the display panel 100 in the
vertical direction is increased.
Referring to the right-side figure of FIG. 5, the second plate
2111b of the main frame 201, the fourth plate 2111d of the first
sub frame 202, and the sixth plate 2111f of the second sub frame
203 are adhered in the folded state to form a fixing part. In
contrast, the frame folding parts 2010 and the third and fifth
plates 2111c and 2111e of the first sub frame 202 and the second
sub frame 203 are not fixed and thus form slip parts, which
independently slip relative to other middle frames. Consequently,
the frame folding parts 2010 and the third and fifth plates 2111c
and 2111e of the first sub frame 202 and the second sub frame 203
slip in the horizontal direction due to the force applied at the
time of folding.
In the foldable display device according to the present invention,
stress generated at the time of folding is applied to the slip
parts of the first and second sub frames 202 and 203, whereby the
stress is dispersed. Consequently, stress applied to inflection
points A at the time of folding is dispersed by the slippage of the
slip parts.
In the foldable display device according to the present invention,
therefore, the amount of stress generated at the time of folding is
effectively reduced, thereby achieving an excellent folding
effect.
Although the present invention will hereinafter be described with
reference to the foldable display device as an example, the
technical concept of the present invention can also be applied to a
lighting device.
As is apparent from the above description, the present invention
has the following effects.
In the foldable display device according to the present invention,
the main frame and the sub frames support the display panel in the
unfolded state. In particular, the opening patterns provided at the
frame folding parts are shifted in the horizontal direction so as
to be misaligned with each other, whereby at least one of the
folding patterns is located over the entire lower surface of the
folding part of the display panel. Consequently, the amount of
force that supports the display panel in the vertical direction is
increased.
In the foldable display device according to the present invention,
the stress generated at the time of folding is applied to the slip
parts of the first and second sub frames, whereby the stress is
dispersed. Consequently, the stress applied to the inflection
points at the time of folding is dispersed by the slippage of the
slip parts. In the foldable display device according to the present
invention, therefore, stress generated at the time of folding is
effectively reduced, thereby achieving an excellent folding
effect.
It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the invention. Thus,
it is intended that the present invention covers the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *